Following the assassination of Nigerian military Head of State, General Murtala Mohammed in 1976, his successor General Olusegun Obasanjo initiated the transition process to terminate military rule in 1979. A new
constitution was drafted, which saw the Westminster system of government (previously used in the First Republic) jettisoned for an American-style Presidential system. The 1979 constitution mandated that political parties and cabinet positions reflect the "federal character" of the nation — Political parties were required to be registered in at least two-thirds of the states, and each state was required to produce at least one cabinet member.
A constituent assembly was elected in 1977 to draft a new constitution, which was published on September 21, 1978, when the ban on political activity was lifted.
In 1979, five political parties competed in a series of elections in which Alhaji Shehu Shagari of the National Party of Nigeria (NPN) was elected president.
Obasanjo peacefully transferred power to Shagari, becoming the first head of state in Nigerian history to willingly step down. All five parties won representation in the National Assembly.
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